import java.io.IOException;

import java.security.Timestamp;
import java.util.Iterator;
import java.util.StringTokenizer;

import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.IntWritable;
import org.apache.hadoop.io.LongWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapred.FileInputFormat;
import org.apache.hadoop.mapred.FileOutputFormat;
import org.apache.hadoop.mapred.JobClient;
import org.apache.hadoop.mapred.JobConf;
import org.apache.hadoop.mapred.MapReduceBase;
import org.apache.hadoop.mapred.Mapper;
import org.apache.hadoop.mapred.OutputCollector;
import org.apache.hadoop.mapred.Reducer;
import org.apache.hadoop.mapred.Reporter;
import org.apache.hadoop.mapred.TextInputFormat;
import org.apache.hadoop.mapred.TextOutputFormat;

public class Map4 {
	

	public static class Map extends MapReduceBase implements
			Mapper<LongWritable, Text, Text, IntWritable> {
		private final static IntWritable one = new IntWritable(1);
		private Text word = new Text();

		/**
		 * O Mapper separa o arquivo BitTorrentTrace.txt a partir do delimitador
		 * '|' e seleciona a primeira coluna. A saida desse map é direcionada
		 * para o reduce com a primeira e a ultima coluna
		 */
		@Override
		public void map(LongWritable key, Text value,
				OutputCollector<Text, IntWritable> output, Reporter reporter)
				throws IOException {
			String[] line = value.toString().split("\t");
			String saida = line[0] + "," +line[1] + "," + line[2];
			word.set(saida);
			output.collect(word, one);
			
			
					}
	}

	public static class Reduce extends MapReduceBase implements
			Reducer<Text, IntWritable, Text, IntWritable> {

		/**
		 * O reduce recebe a chave e o valor do map e os direciona de forma que
		 * a contagem não seja inclusa no resultado e a ordenação é feita pelo
		 * próprio map, a saída do reduce vai para o arquivo part-00000
		 */
		public void reduce(Text key, Iterator<IntWritable> values,
				OutputCollector<Text, IntWritable> output, Reporter reporter)
				throws IOException {
			int sum = 0;
			while (values.hasNext()) {
				sum += values.next().get();
			}
			output.collect(key, new IntWritable(sum));
		}
	}

	public static void main(String[] args) throws IOException {
		JobConf conf = new JobConf(Map4.class);
		conf.setJobName("Map4");

		conf.setOutputKeyClass(Text.class);
		conf.setOutputValueClass(Text.class);

		conf.setMapperClass(Map.class);
		// conf.setCombinerClass(Reduce.class);
		conf.setReducerClass(Reduce.class);

		conf.setInputFormat(TextInputFormat.class);

		conf.setOutputFormat(TextOutputFormat.class);

		FileInputFormat.setInputPaths(conf, new Path(args[0]));
		FileOutputFormat.setOutputPath(conf, new Path(args[1]));

		JobClient.runJob(conf);
	}
}
